/*
 * Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 */
package qunar.tc.decompiler.modules.decompiler.exps;

import qunar.tc.decompiler.main.collectors.BytecodeMappingTracer;
import qunar.tc.decompiler.modules.decompiler.vars.CheckTypesResult;
import qunar.tc.decompiler.struct.gen.VarType;
import qunar.tc.decompiler.util.InterpreterUtil;
import qunar.tc.decompiler.util.TextBuffer;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;

public class SwitchExprent extends Exprent {

    private Exprent value;
    private List<List<Exprent>> caseValues = new ArrayList<>();

    public SwitchExprent(Exprent value, Set<Integer> bytecodeOffsets) {
        super(EXPRENT_SWITCH);
        this.value = value;

        addBytecodeOffsets(bytecodeOffsets);
    }

    @Override
    public Exprent copy() {
        SwitchExprent swExpr = new SwitchExprent(value.copy(), bytecode);

        List<List<Exprent>> lstCaseValues = new ArrayList<>();
        for (List<Exprent> lst : caseValues) {
            lstCaseValues.add(new ArrayList<>(lst));
        }
        swExpr.setCaseValues(lstCaseValues);

        return swExpr;
    }

    @Override
    public VarType getExprType() {
        return value.getExprType();
    }

    @Override
    public CheckTypesResult checkExprTypeBounds() {
        CheckTypesResult result = new CheckTypesResult();

        result.addMinTypeExprent(value, VarType.VARTYPE_BYTECHAR);
        result.addMaxTypeExprent(value, VarType.VARTYPE_INT);

        VarType valType = value.getExprType();
        for (List<Exprent> lst : caseValues) {
            for (Exprent expr : lst) {
                if (expr != null) {
                    VarType caseType = expr.getExprType();
                    if (!caseType.equals(valType)) {
                        valType = VarType.getCommonSupertype(caseType, valType);
                        result.addMinTypeExprent(value, valType);
                    }
                }
            }
        }

        return result;
    }

    @Override
    public List<Exprent> getAllExprents() {
        List<Exprent> lst = new ArrayList<>();
        lst.add(value);
        return lst;
    }

    @Override
    public TextBuffer toJava(int indent, BytecodeMappingTracer tracer) {
        tracer.addMapping(bytecode);
        return value.toJava(indent, tracer).enclose("switch(", ")");
    }

    @Override
    public void replaceExprent(Exprent oldExpr, Exprent newExpr) {
        if (oldExpr == value) {
            value = newExpr;
        }
    }

    @Override
    public boolean equals(Object o) {
        if (o == this) {
            return true;
        }

        if (!(o instanceof SwitchExprent)) {
            return false;
        }

        SwitchExprent sw = (SwitchExprent) o;
        return InterpreterUtil.equalObjects(value, sw.getValue());
    }

    public Exprent getValue() {
        return value;
    }

    public void setCaseValues(List<List<Exprent>> caseValues) {
        this.caseValues = caseValues;
    }
}
